Compression devices to carry out the anastomosis of said organs have been studied in the past. Said known devices are composed of biodegradable parts, that are suited to compress the edges of the hollow organs to be connected, so that said devices are reduced to fragments that can be more easily expelled with the stool. This technique is known for example from U.S. Pat. No. 3,974,835. The biodegradation rate of said materials varies from individual to individual and within the same individual according to the different physiological condition implying alteration of the metabolism and, therefore, a change in the rate of the chemical reactions causing the biodegradation. There is therefore a problem in that it can not be precisely forecast how much time will be necessary for the fragments of said devices to be reduced: in fact, it might even occur before, or a considerable time after, the natural consolidation of the edges of the organs to be anastomosed occurs. In both cases disadvantageous conditions would be created: in the first case the surgery would have failed because the holding device would be fragmented before the consolidation, that is no healing of the organs to be anastomosed would occur, and in the second case an obstacle would be introduced into the digestive tract in an unforeseeable seat and for a longer time than necessary.
Moreover, said devices made of biodegradable material must necessarily have thin walls, thereby having the draw-back of being very fragile and difficult to manufacture.
To the purpose of eliminating the above-mentioned draw-backs, a device has been studied and manufactured, said device being the object of the European patent application No 0362163 of the same inventors of the present application.
The above device, which exhibits the features of being reduced to fragments as soon as the edges of the organs to be anastomosed lose their consistency, is composed of a first member having a hollow cylindrical shape that is adapted to contain a second member, also having a hollow cylindrical shape, in such a way that between said two members the edges of said two hollow organs to be anastomosed can be inserted. In particular, the first member is composed of two sub-members that are lockingly inserted into one another. Such a device can easily be applied to an apparatus, such as the one described in U.S. Pat. No. 4,681,108, studied and manufactured by the same inventors of the present application, that allows the subject device to be positioned and, consequently, employed.
The above-mentioned sub-members are composed of sectors that are solidly connected to one another by means of teeth provided on the circumferential part of the sectors of the internal sub-member that are engaged in through-windows formed on the circumferential part of the sectors of the outer sub-member, thereby locking it onto the other sub-member.
Also this solution, while being a valid one in that it has improved the prior technology, exhibits some draw-backs, such as for example the instability of the anastomotic device. In fact, said device, while it warrants a good stability in the normal physiological and pathological state of the patient, if it is handled by the surgeon with insufficient caution, it can be fragmented, for example when the compressed tissue of the organs to be anastomosed is very this.
A further draw-back results from the need of using, for manufacturing its outer sub-member, a material having a high tensile strength since this sub-member comprises the above-mentioned windows that are the weak point of the device.
Moreover, it is very difficult and expensive to produce a mould for the mass production of said outer sub-member in plastic material.